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| The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland |
Gametophyte. Plants medium sized to robust, leafy. One- to two-pinnately branching. Plants with flagella or flagelliform shoots or branches (in that the mature branches have attenuate apices with smaller leaves, and sometimes flagelliform tips), or with neither flagella nor flagelliform shoots or branches; with paraphyllia amongst the leaves (on the main axes). Acrogynous. The leaf cells with trigones (these large). Rhizoids arising near the branch tips.
The leafy shoots dorsiventral, with two equal ranks of lateral leaves and a third, ventral rank of smaller underleaves. The vegetative leaves markedly asymmetrical. The vegetative leaves more or less transversely inserted (approximate, translucent, very fragile); alternate; approximate to overlapping. The leaf margins multi-ciliate. The vegetative leaves undivided to several-lobed (mostly 3–4 lobed); without vittae. Underleaves smaller than the laterals though well developed and conspicuous (shorter, bilobed). Gemmae absent.
The plants dioecious.
Male inflorescences on short lateral branches, the antheridia 2–3 in the axils of male bracts and underleaves. Male bracts subtending 2 antheridia, or several antheridia. Female inflorescences terminal on short lateral branches. Perianth present to absent; if detectable, rudimentary.
Sporophyte. The sporophyte elevated by elongation of the seta, with no intercalary meristem. The capsule ovoid; dehiscing by four valves. Elaters present; bispirally thickened; free.
British representation. 1 species (M. woodsii); Scotland and Ireland.
Classification. Class/Division Hepaticae. Subclass/Class Jungermanniidae. Order Jungermanniales. Family Lepicoleaceae.
Comments. Smith’s description of the sporophyte quoted here is alarmingly different from Macvicar’s regarding ‘perianth’, etc. ..... Illustrations. • M. woodsii: Jameson, in Macvicar (1926). • M. woodsii: Pearson fig. XXXVII (1902). • M. woodsii: Pearson fig. XXXVII legend.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2005 onwards. The liverwort genera (Bryophyta: Hepaticae and Anthocerotae) of Britain and Ireland. Version: 5th August 2019. delta-intkey.com’.
